.Buildings.Fluid.Interfaces.Examples.ReverseFlowMassExchanger

Information

This model tests whether the results for a mass exchanger are identical for forward flow and reverse flow.

Note that if the latent heat transfer effectiveness is non-zero, then the results will differ. The reason is that the maximum capacity stream is computed using the mass flow rates at port_a1 and port_a2. For reverse flow, they are not equal if moisture is added to the mass flow rate. Using an average mass flow rate in computing the heat and moisture transfer would lead to identical results, but it would introduce additional nonlinear equations that need to be solved. Therefore, the model uses the mass flow rates at port_a1 and port_a2.

Note: This problem fails to translate in Dymola 2012 due to an error in Dymola's support of stream connector. This bug will be corrected in future versions of Dymola.

Contents

Revisions

• September 20, 2020, by Michael Wetter:
  Updated model to use one port temperature sensor from Modelica Standard Library.
  This is for #1399.
• May 2, 2019, by Jianjun Hu:
  Replaced fluid source. This is for #1072.
• November 2, 2016, by Michael Wetter:
  Changed assertions to blocks that compute the difference, and added the difference to the regression results.
  This is for issue 564.
• October 9, 2013, by Michael Wetter:
  Replaced Modelica.Fluid.Sources.FixedBoundary with Buildings.Fluid.Sources.FixedBoundary as otherwise, the pedantic model check fails in Dymola 2014 FD01 beta3.
• August 19, 2010, by Michael Wetter:
  First implementation.